System of motor control.



NO. 316,804L ETENTED APR. 3, 1906.4

A. MAGNUSON. SYSTEM OT MOTOR CONTROL.

APPLICATION FILED JAN. 18, 1905.

` INVENTOR ATTORNEY- UNITED STATES y' PATENT OEIgICE.-

AXEL MAGNUSON, OF NEW YORK, N. Y., ASASIGrNOR, BY-MSNE ASSIGN- :MENTS `TO OTIS ELEVATOR COMPANY, OE JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

SYSTEM oF MoToR CONTROL.-

' Specification of Letters Patent.

Patented April 3, 1966. i

Application filed January. 18,1905. Serial No. 241,592.

Tooll whom it may concern,.-

Be it known that I, AXEL MAGNCSON, a citizen of the United States, and a resident of .'New York city, in the county of New York.

Land State of New York, have invented certain new and useful' Iniprovements in Svsgreat advantage in conjunction with alter-l natin '-current motors.

Re erring to the drawings, Figure' 1 is a side elevation of an electric motor with cerzo tain connected parts and with the various parts of the apparatus which I use in carry- Ing out my invention shown in connection therewith. Fig. 2 is an end view of a generator which I use and shows certain details oi construction which will be described later.

Fig. 3 is an elevation showing a motor connected to run a shaft and with a generator connected to the driven shaft. Fig. 4 is a diagram of a preferred form oi electrical circuits and Certain apparatus which illustrates the use f'my invention.

' Like characters of reference designate corresponding parts in all of the figures.

10 desi nat-es a motor which is to be Con- `-gtrolled. 4In the drawings it is shown as an alternating-current motor.

20 is a direct-current generator which is driven by the motor 10. It may be directly connected to the motor by having its shaft o 21 connected tb the motor-shaft 11 by a coupling 22, as shown in Fig. 1,0r it may be connected to a--moving part of some mechanism which is driven by the motor 10. Such 'an arrangement is shown vin Fig. 3, in which the motor is.connected to drive a shaft 15 by means of a belt 13, running over a pulley 12 on the motor-shaft 11 and another pulley 14 on the driven shaft 15. In this case the generafor is arranged to be driven from the shaft 5o 15 by means of a belt 24 and pulleys and 25.' l

30 designates a transformer the primary of which 1s connected to a suitable source of l electrical supply. Its seconda is connected, through a switch 31, to an e ectriccontroller 40, which contains certain magnets, switches, and other apparatus, all of which will be pointed out later.

50 a manually-operated circuit closer or switch which ma f be situated in any convenient place and` .by means of which the 6o motor mav be started, stopped, or reversed= at will. 'Ihjs manually-operated switch 50 comprises a movable contact-arm 5.1,' ivoted at. 52 and divided into two arts. he upper part is arranged to ma e an electrical connection between Va segmental contactieee 53, which 'is connected to one ofthe eads 33 from the transformer 30 and either the stationary contact 54 or vthe stationary contact 55. At the same time the lower part 7.o of the movable contact ar'm 51- will make connection between Va segmental contact-- piece and either the stationary contact 57 orv the stationary contact 58. I., Y

Let us, for example, consider that'the top 75 of the movable contact 51 has been moved to the left. Stationary contact 54 will then be connected with one of the mains 33. A cir cuit will then be established from these through wire 41 to the lower terminal of a 8o magnet 42, thence through conductor 43 to the main 34. Thus the magnet 42 will be connected in one phase of the line and become energized and'attract its armature 44.

"lhe lat-ter is pivoted at 45. When' it 'is 85 moved by the magnet 42, it will move the contacts 46 and 47 against the contacts 46 and 47', respectively.' This will close circuits rom the main 32 to the terminal 16 on the motor and from the mein 34 to the terminal 17 on the motor, and as the terminals 18 18 `are already connected' to the main 33 it will be seen that the motor is now connected to the three mains, and, with the other circuits connected as shown, the motor will begin to rotate.

As the generator 20 is connected to run with the motor, it will now begin to rotate and to generate an electromotive force. A conductor 26 isled from one oft-he brushes loo 26 of the generator to a number of magnets 42 is one of these magnets, and one of its ter minals is connected to' this conductor 26 -Its other terminal is connected by a condiu to`rj to the stationary contact 57. This the inner part of this starting resistance will 'contact is now connected by movable contact 51 to the segmental contact 56, and this is connected by conductor 28, through the series field 27 of the generator, to the other brush 27. The magnet 42lv then is directly connected to the generator and will receive current from it as' -the enerator revolves. The magnet 42 'then wi he energized ari'd will pull its core ,44' to the right, and as it is connected at 45 tothe arm which carries the armature 44 it will assist the magnet 42. As

the current in magnet 42 is a direct current,

it will-hold the contacts 46 47 against the contacts 46 47 firmly without the chattering which would be caused by the alternating current in the magnet 42.

If the movable lever 51 had been moved to the ri ht, the operation would be similar to that a ove described, except that in this case the magnet 62 would be energized and the contacts 66 67 would be closed against the contacts 66 and'67. This will connect main 32A to motor-terminal 17 and main 34 to motoreterminal 16 and will cause the motor to rotate in the opposite direction.

It will be seen that an opposition element isinter cs ed in the rotor-circuit of the motor in the orm of the star-connected resistance 73. This o position element may be resistance or in uctance or any other desired arrangement Which may be used to revent too great a flow of current. 'Vhen t 1e motor is started, all of this resistance is preferably inserted in the rotor-circuit. The motor will not then get full power at once, but will begin to rotate slowly. The resistance should then be cut out of the circuit gradually in order to give the motor the proper acceleration. I will now describe my improved method of accomplishing this result.

By examining the diagram it may be seen that the leads from the generator are connected to three magnets 80, 90, and 100. The lead 26 is connectedto the yleft-hand end of each of these magnets,'and the lead 28 is connected to the right-hand side of each of these magnets. I will now describe the magnet 80, with its various connected parts. This comprises a coil to which the leads just referred to are connected, and a core 84. This core is.mechanically connected at "'-to a vertical arm, which is pivoted to astationary point at 85. The upper part of this arfm carries three contacts 86, 87, and 88, which are electrically connected together.

the magnet 80 is ergized, it will pull the vertical arm Whig carries these contacts over to the left until they connectA with three stationary contacts 86', 87', and 88. These three stationary contacts are electrically connected to the points 72, 70", and 7.1B on' the startin resistance. It is evident, them-that when t ie magnet 80 has connected the con-- tacts 86 8,7 8 8with the contacts 86'; 8723,88

be short-circuited thereby. In a similar manner the magnet 90 is arranged to ldraw contacts 96 97 98 against contacts 96 97l 98 and to electrically connect them and to thereby short-circuit another section of thestartmg resistance, as they are connectedV to the points 72A, 70A, and 71^, respectively. The

4magnet 100 is similarly'arranged to shortcircuitahe third and lastsectionof this starting resistance by drawing contacts 106, 107, and 108 against contacts 106', 107', and 108.

These magnets then are for the purpose of short-circuiting the starting resistance in a number of steps. They. are preferably arran ed or adjusted to be drawn in one by one as t e potential of the enerator 20 increases.

out, to operate one at a 'time as the voltage' increases it is evident that the starting resistance will be cut out by these magnets in direct proportion to the speed ol the motor,

As the genera.-

and the acceleration of the motor ofcourse depends upon the load which it has to'drive. The generator 20 may be of any desired form-as, for exam le, a dynamo withpermanently-excited fie dsor it maybe exclted by a shunt-field or a series field 27', as shown in thediagram. It is desirable in most'cases to hav\the direction of current owin from this generator a constant one, and have shown in Fig. 2 one method of accomplishin this result. The armature-brushes 26 an 27 are mountedupon the yoke 26^, which is rovided with antifriction-rollers. ,This yo ie is arranged t travel through asemicircle as the motor rota es in one direction or the other. An arm 27^\is connected to this yoke and is adapted to come in contact with pins or Stops 27 and 27C when the brushes are at the proper point on thecommutator of the motor. If the motor-armature is rotatin in IOO such a direction as to be anticlockwise w en l looked at from the view shown in Fi 2, the arm 27 will be brought against t e stop 27 and the brushes 26 and- 27 will be held in the position shown in the drawings. If the \motorarmature rotates' in the opposite direction, thearm 27A will be carried around until it comes into engagement with the stop 27,.when the position of the brushes 26 and 27 will be interchanged.

Thiskinvention is applicable to any form of electric motor and to many forms o starting devices v'firch may be o `erated by a variable voltage. he various orms of switches and circuits whiclilA have shown are merely shown to illustrate my invention, and I do not Wish to limit myself to any particular form. While in the drawings I have shownv aresistance in the rotor circuit of an alternating current motor, I do not wish to confine myself to the use of a resistance, as many other devices may'be used for the purpose of starting the motor. In' some cases, even, it is desirable to admit more current to the motor in starting than is -admitted to it while running, and vthis invention is applicable to such an' arrangement. While the drawingsl show the motor as connected to a multipliase supplycircuit, the actuating-magnets of the reversin -switches are connected in a single phase on y, and it is evident that the controllin 2. The combination with a multi hase motor, of controlling apparatus there or, means vin a circuit connected acrossany two of the mains of Said motor, for closin a single-phase circuit to said motor-control ing a paratus, and electric holding means for sai controlling apparatus.

3. e combination with an electric motor, of controlling apparatus therefor, holding means for said controlling apparatus, a source of single-phase current, a source of direct current', and a single switch device for controlling the singlehase current to operate said motor-contro ing apparatus an( for controlling the direct current to operate said holding means.

4. lThe combination with an electric inotor, of starting-switches therefor, electroresponsive devices for closing said switches, e ectromagnetic apparatus or holding said switches 1n closed position, a source of singlephase current, a source of direct current and a single manual switch for controlling the single-phase current to operate' said electroresponsive devices and foricontrolling the direct current tov-operate said electromagnetic I holdin apparatus. f

5 T e combination witlian alternatingcurrent motor, (if reversin -switches therefor, singlephase magnets giir actuating said switches to clpsed position, direct-current magnets for holding said switches in closed position, and means for controlling both the said single-phase magnets and the said direct- 'current magnets.

- 6. The combination with an alternatingcurrent in'otor, of two reversingswitches tl'ierefor,'an electroresponsive device for each of said switches to actuate` the saine to closed position, an electroinagnet connected to each switch to hold the saine in closed position, and a manual switch for controlling singlephase current to operate either of the electroresponsive devices and foracontrolling direct current to operate the corresponding holdingelectromagnet. A

7. In combination with a motor, a source of electrical supply, a resistance in series with the motor-armature, and a generator connected to the motor and arranged to controlv said resistance in starting the motor.

8. In combination with a motor, a source of electrical supply, a resistance in series with the motor-armature, and a generator'mechanically connected to the motor and arranged to control said resistance in-starting and stopping tlie motor. 1

9. In combination with an alternatingcurrent motor, a source of electrical su ply, a resistance electrically connected to tile motor, and a generator connected to the motor and arranged to control the movement of the motor upon starting, -by controlling the resistance.

10.' In combination with a motor, an opposition element in 4circuit with the motor and a generator mechanically connected to the motor and arranged to control the-movement of.. the motor in starting and stopping by controllin the opposition element. 4

11. n combination with an alternatingcurrent motor, a resistance electrically connected to the motor, and a generator connected to the motor and arranged to control the resistance in proportion to the speed Vof the motor on starting. Y

12. In combination with a motor,l con- IOO trollingcircuits therefor, electromagnetic switches in the controllin -circuits means for generating a variable vo tage in proportion to the speed of the motor, saidyoltage a plied to said electromagnetic switches 111.1: e controlling-circuits which are arranged to be actuated by tl'ie va'riable voltage.

13. In combination with a motor, an opposition element in circuit with the generator` so connected to the motor that it will enerate a voltage in proportion to the speed of the motor, a plurality of electromagnets in connection with the generator and arranged to'control the op'posi1 ion element.

I4'. The con'ibination with` an electric motor,and a mechanism driven thereby, a gen- 'erator mechanically connected to the driven '-inechanisin, an electrorcceptive device connected to said generator, and ineans electric-v motor, a

ally connected to the motor and operated .by

said electiorecep'tive device for controlling the acceleratioi of tlie motor upon starting.

15. In combination with an electric motor,

a meclianisni drivlen thereby, an opposition element in the motor-circuit, an electrores oiisive device for controlling the op osition e ement, and a generator connecte tothe i lvice during the rotation of the motor.

1.7. In combination with an electric motor,

I a'starting device therefor, electric circuits to actuate ,the starting device, asource of electrical'su ply, and another source of electrical supply ependent upon the movement of the motor and proportionalto its speed and arranged to coperate with the first source of supply to hold the starting device during the j; rotation of thc motor.

18. In combination with an electric motor,

' an electrically-operated starting device therefor, electric circuits to actuate the starting device, a source of electrical supply, another source of electrical supply dependent u on the speed of the motor and proportiona to its speed and arranged to cooperate with the first source of supply to hold the starting device during the rotation of the motor, and a manually-operated switch to control the circuits to the starting device. v

19. A starting device for motors comprising an alternating-current motor, a directcurrent generator connected to run with the motor, and means actuated bv the current from the generator to control the starting and accelerating ofthe motor.

20. In combination with an alternatingcurrent motor, a source of alternating-current supply, an opposition element in the inotor-circut, a series of electromagnetic responsive devices for removing the op o'sition element from the motor-circuit, ani a source of direct-current supply dependent upon the movement of the motor and proportional to its speed, arranged to actiiate the electrores onsive devices one by one as the speed of t e motor increases.

2 1. In combination with an alternatingcurrent motor, a source of alternating-current supply, a starting device for the motor arranged to be actuated by the alternating current, means dependent upon the movement of the motor for enerating a direct current, and a magnetic evice operated by such direct current to hold the starting device firmly in closed position.

22. In combination with an alternating- Acurrent motor, a source of alternating-current sup ly, a starting device for the inotor arrange to be actuated bythe alternating current', a direct-current generator dependent upon the movement of the motor arranged eiegeofi to generate a voltage proportional to the speed of the motor, a`magnetic device connected to such direct-current generator and arranged to hold the stai'ting device firmly in closed position, an opposition element in the motor-circuit, and a series of electroresponsive devices for removing the opposition element from the motor-circuit, said electroresponsive devices being connected to the direct-current generator and arranged to be actuated one by one as the motor accelerates.

23. In combination with an alternatingcurrent motor, an electrically-operated starting device therefor, and circuits for'actuat ing the starting device comprising an altermating-current circuit and a direct-current circuit.

424:. In'combination with an alternatin current motor, a starting device therefor, allternating-current and direct-current circuits, said startin(1r device being actuated by a sinlehase alternating current and positively el in operative position b a directv current.

25. In combination wit current motor, a starting 4device therefor, said startinfr device being actuated by a singlehase alternating current and positively hel in operative position by a direct current, alternating-current and direct-current electrical circuits for the starting de vice, and a manually-operated switch for controlling the circuits.

an alternating- 26. In combination with an alternating# current motor, a device for starting the motor in one direction, and another device for starting the motor in the other direction, alternating-current anddirect-currerit circuits said startinU devices being actuated by a singlehase alternating current and positively held in operative position by a direct current.

27. In combination with an alternating- Acurrent motor, a resistance, an electricallyoperated reversing-switch, circuits for the reversing-switch for both alternating and direct currents, a manually operated switch for controlling the circuits, electroresponsive devices for controlling the resistance, and a direct-current generator connected to run with themotor, arranged to supply the directcurrent circuits for the reversni -switch and.

to automatically actuate the e ectroresponsive devices.

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28. In combination with an alternatingl current motor, a resistance, an electricall operated reversing-switch, circuits for t e reversing-switch for both alternatin and direct currents, a manually-operate switch for controlling the circuits, electroresponsiv'e devices for controlling the resistance, and a direct-current generator connected to runs with the motor arranged to supply the directcurrent circuits for the reversin -switch and to automatically actuate 'the e ectroresponsive devices in proportion to the acceleration of the motor.

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29. In combination with an alternating-` ed to run with the motor arranged to supply the direct-current circuits for the reversingswitch and to automatically actuate the eleci troresponsive devices one at a time in propory tion to the acceleration of the motor.

30. In combination with a motor, means for reversing the direction of rotation oi tlie motor, a generator connected to run with the motor, means for keeping the direction of the current generated by the generator the same if the direction of rotation of the motor is changed, and means actuated by the current generated by the generator for controlling the motor. Y

31.. In combination with a motor, means for reversing the direction of rotation of the motor, a resistance for the motor-circuit, a generator connected to run with the motor, means for keeping the direction of the current enerated by the generator the same if the irection of rotation of the motor is changed, and means actuateod by the currentl generated by the generator for controlling the motor by cutting the resistance into and out of the motor-circuit.

32. In combination with a motor, means for reversing the direction ot rotation of the motor, a generator connected to run with the motor, means connected'with the generator for keeping the direction of its generated cur- -rent the same, said generator arranged to generate a voltage in proportion to the speed of the motor, and electroresponsive devices 'dependent upon the generated voltage for controlling the acceleration of the motor.

33. In combination with an alternatingcurrent motor, a starting devicetlierefor, and a direct-current generator connected to run with the motor and arranged to control the acceleration of the motor, in starting the motor.

34. In combination with an-alternating current motor, a starting device therefor actuated by .alternating current, and a directcurrent generator connected to run with the motor and arranged to control the acceleration ot the motor.

35. In combination with an alternatingcurrent motor, means for starting the motor in one direction or the other, and a directcurrent generator connected to run 'with the niotor and arranged to control the acceleration of .the motor'.

36; In combination with an alternating- .it motor, means for starting the motor in one direction or the other, said means actuated by alternating current, and a directcurrent Agenerator connected to run with the motor and arranged to lcontrol the accelera-i tion of the motor.

37. In combination with an alternating- I current motor, means for startin the motor in one direction or the other, sai means aotiiated by an alternating current, a manually-operated switch for controlling the startmg device, and A:adirect-current generator connected to runV with the motor and arranged to control the' acceleration of the motor. v

3S. In combination with analternatin current motor, a starting device therefor`,`a

teriiating-current and direct-current circuits,

said starting device being actuated .by an alt ative position by va direct current.v l i 39. In combinationwith an alternatingcurrent motor, a starting device therefor,

said starting device being actuated by an alternating current and positively held 1n opertern atingcurreiit-and positively held in operative position by a direct current, alternating-current and 'direct-current lectrical circuits for the starting device operated switch for controlling the circuits.

40. In combination with an alternatingcurrent motor, a device for startin the moan a manuallytor inione direction, and another evice for starting the motorinthe other direction, alternating-current and direct-current circuits, said start-ing devices being actuated byun alternating current and positively held in 30perative position by a direct current.

41. In a starting device for alternatingcurrent motors, a source of supply, a starting mechanism, alternating-current and directcurrent circuits, means connected with said zoo 'y source of supply arranged to actuate'the starting mechanism to start the motor, and a direct-current generator mechanically connected to the motor and arranged to control the acceleration oi the motor step by step.

42. In a system of motor control, two sources of .current-supply, one being ulsating and connected to the motor, the ot er being a direct current generated by the movement of the motor and variable from zero to a maximum in proportion to the speed ofthe motor and adapted to control t e acceleration of the motor. l

43. In a system of motor control, two sources of current-supply, one of which is not variable and is .connected to the motor, the other of which is generated by the movement of the motor and is' variable from zero to a. iiiaxiiiium in proportion to the speed of the motor. A

44. In a system of motor control, two sources of current-supply, one of which is not variable and is connected to the motor, the

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other of which comprises a generator conthe motor.

.chanically connectedto 45. In a system 'of motor control, two sources of current-supply, one being obtainable before the motor is started and the other being dependent upon the movement of said motor, means operated by current from one of said sources for starting, reversing or stopping the motor, and means o erated by current from the other source gbr ellecting an acceleration of the' motorA 46. In'combination with an electric motor, an external source of current-sup ly of practically constant value, a contro ing device in series with the motor, and a generator me the motor and arranged to control the controlling device.

47. In combination with an electric motor, an external source of currcnt-supply of ractically constant value, a starting-switc 1 for the motor, a controlling device for the motor,

and a generator mechanically connected to the motor and arranged to control the controllin device.

48. n combination with an electric motor, an external source of current-sup tically constant Value, an electrically-actuated starting-switch for the motor, a manually-operated circuit-closer for the startingswitch, a controlling device for the motor,' and -a generator mechanically connected to the motor and arranged to control the controlling device. v

In witness whereof I have signed my name to this specification in` the presence of two subscribing Witnesses.

AXEL MAGNUSON. VVitnessesi- WALTER .C. STRANG, ERNEST W. MARSHALL.

ply of prac- 

